Method for the transformation of heat



Jan. 14, 1936. E, ALTENKIRCH ETAL/ 2,027,571

METHOD FOR THE TRANSFORMATION 0F HEAT Filed oct. 17; 1 932 l mmm rug.

l Mm wm am mmwmm Patented Jan.I A14, 1936 PATENT OFFICE 2,027,571 METHODFOR THE TRANSFORMATION OF BEAT Edmund Alunnwn, Neuenhue and Kurt N `n,near- Berlin, 'Berlin-Siemensstadt,

Germany, asslgnors toSiemens-Schnckertwerke Aktiengesellschaft,`Bcrlin-Siemensstallt, Germany, a corporation of Germany Application In2 Claims.

Our invention relates to a method for the transformation of heat bymeans of an apparatus of the intermittent absorption type. The'mainobject of our invention is to pro- 5 vide a methodfor transforming heatfrom a lower to a higherl temperature and vvice versa by the use oi anapparatus of the intermittent absorption type. According to theinvention the vapor of the working medium is separated at a low pressurefrom the absorbing medium during the condensation period and condensed;whereupon the liquid working medium evaporates at a higher pressureduring the absorption period and is again absorbed by tlieabsorbing'medium.'

3,5 In 4this manner, it is possible to use an apparatus oftheintermittent absorption 4type for transforming heat -of low temperatureto heat oi higher temperature in a particular way. This may beaccomplished, for instance, either by producing from cold availableatvery low temperature a greater quantity or cooling of somewhat highertemperature or by producing heat of higher temperature from heat oflower temperature.

In the last-mentioned case, it is possible among other things to utilizethe natural difference in temperature existing between a low outsidetemperature on the one hand and an average ground water temperature ontheother hand for the production of heat. In this case the method iscarried out in such a manner that the absorber-generator during thecondensationA period is supplied with heat of average temperatureand theheat of condensation is abstracted 36 from the condenser vat a lowertemperature;

whereupon the evaporator during the. absorption period is supplied withheat of average temperature andthe heat is withdrawn from theabsorber-generator at a higher temperature.

40 The inst-mentioned case regarding the production of a greaterquantity of cooling may, for instance, be applied to a refrigeratingsystem operating with solid carbon dioxide. In this case, the heat iswithdrawn during the condensation period from the condenser by means ofa cooling medium (for instance carbon dioxide) and theabsorber-generatcr is supplied with heat from the space to be cooled;whereupon during the absorption period the heat is taken up from thespace. tobe cooled by the evaporator and the heat of absorption iscarried off by the absorber-generator to -the atmosphere. l

in the accompanying drawing two embodiments for the method according toour invention are shown in diagrammatical form.

October 17. V193%, Serial No. 638,260 Germany October 20, 193i (Cl,(i2-120) Fig. 1 illustrates' a system in which the metnod for producingcold is utilized, and Fig. 2 shows a system in which themethodcorresponding to the invention is employed for vided inside bymeans of heat-conducting walls 22 into individual cells into which asolid absorbent, for instance calcium chloride or strontium bromide, isintroduced which forms with the refrigerant' (for instance ammonia) achem- 15 ical compound. The heat conducting walls are provided withopenings 24 which are I arranged in relation to the filling opening 25.The solidabsorbent is introduced into the lling opening 25 and fallsthrough the openings 20 2l, and is distributed over the single cells.Midway between the walls of the absorber-generator a perforated conduit26 mai-mused to which a; conduit 3 is connected leading to thecondenser-evaporator 2; On theouter wall ol.' 25 the absorber-generatorI as well as `on that of the condenserevaporator 2 radiating ribs 23 and2l respectively are arranged so as to assist both the application andthe dissipation of heat. Both vessels I and 2 are placed each in a cham-30 ber l and 8 respectively which are heat-insulated with respect to thesurrounding vatmosphere as well as to the storage space E ci theapparatus. The chamber 'l' has four openings 15,16, I1, I8 and thechamber 8 two, I9 and 2d 35 controlled with exception of the opening I9by valve-like members 9, I0, Ii, I2 and It connected with one anotherand operated by a common handle Il, so that the chamber 'I maycommunicate on the one hand with the storage 40 space 5 through theopenings I5, I6 and on the other hand with .outside air through the.openings Ii and I8, and the `chamber 8 may communicate with the storagespace 5 through the openings I 9 and 20. The reversal of the 45valve-like members may also be 4automatically effected; for instance, inaccordance withthe decrease in weight of the carbon dioxide snow or withthetemperature of the evaporator. In the condenser-evaporator 2 a Vspace2l is pro- 50 vided for the reception of the carbon dioxide. The nllingof this space is effected through a iilling passage 6 arranged in theinsulation; said passage may be provided with a cover to exclude theoutside air.,

The operation of the above-described apparatus is as follows: In puttingthe apparatus into operation, the carbon dioxide snow is introduced intothe space 2| so that the condenser-evaporator 2 is intensely cooleddown. In this manner the pressure prevailing in the apparatus is so low,that the refrigerant is expelled in the absorber-generator I from thechemical compound. The refrigerant vapor is condensed in thecondenser-evaporator 2 cooled by the carbon dioxide snow. During thecondensation period, the valve system 8-I3 is brought to the position asshown in Fig. 1. 'I'he lower opening 20 provided in the condenserchamber 8 consequently, closed by the valve member 9 in order to protectthe condenserevaporator from the higher temperature prevailing in thestorage space 5. Avalve member is not necessary for the opening I8,since a circulation kof air and consequently a transfer of heat from thestorage space' 5 to the chamber 8 is prevented by the closure of thevalve member 9. The evaporated carbon dioxide snow flows through theopening I8 and the refrigerator into the atmosphere, so that the wastecold of the carbon dioxide vapor is furthermore utilized for cooling thestorage chamber. The absorption chamber 1 is closed againstoutside airduring the condensation period by the valve-like members I2, I3, whereasthe openings I5 and- I5 communicate with the storage chamber 5, so thata circulation of air between the chamber 1 and the storage chamber 5 maytake place so as to transfer the cooling from the absorption chamber 1to the storage chamber 5.

itl the end ofthe condensation period the valve system is reversedsorthat now the openings I 5 and I6 of the chamber 1 are closed by theValve members I 0 and II,` whereas the absorption chamber 1 communicateswith outside air by the openings I1 and I8.

chamber A communication between the condensation 8 and the storagechamber 5 is also established at the same time by opening the valvemember 8. The liquid refrigerant collected in the condenser 2evaporates, and returns through the conduit 3 to the generatorabsorberI, where it is again absorbed. The condenser-evaporator2 abstracts theheat of evaporation from the air in the chamber 8 which is thus cooleddown. 'I'he cold air flows from the lower opening 20 of the chamber 8 tothe storage chamber 5, whereas the hotter storage chamber through theupper opening I8. This circulation causes the storage chamber to cooldown. The heat of absorption is transferred from the absorber-generatorto outside air. The air heated by the absorber-generator walls 22 andthe cooling ribs 23 rises upwardly, and passes into the atmospherethrough the opening I1, whereas the colder outside air flows into thelower part of the chamber 1 through the opening I8. To assists the aircirculation, the openings I 5 and 20 on the one hand and I3 and I5 onthe other hand are not exactly disposed particularly one above theother, but are displaced. Further, to effect a proper circulation ofpartition may be arranged.

This apparatus presents the following advantages: If the refrigeratorshould only be cooled by carbon dioxide snow, the'cold energy stored upin the carbon dioxide snow would be utilized. However, by employing theabove described method not only is the` energy stored up by air returnsto the chamber 8 air a perpendicular,

carbon dioxide utilized for the refrigeration, but also the cold energystored up during the charging process of the absorption apparatus. Inthisv manner the 'refrigeration effected by each kg. carbon dioxide snowis considerably enhanced, i. e., to about the double amount.

Fig. 2 shows a system in which the method according to'A the inventionis utilized for the production of heat.- In this case an apparatus ofthe intermittent absorption type is employed which operates with aliquid absorbent; for instance with van aqueous ammonia solution. 44denotes the absorber-generator and 52 the correspondingcondenser-evaporator of the absorption apparatus. 53 is a conduit forthe expelled working medium and 54 a return conduit for the evaporatedworking medium. The return conduit 54 enters a perforated gasdistributing conduit 48 at a point4 below the lowest liquid level in theabsorber-generator 44. In this embodiment, the difference between thetemperature of the outside air and that of the ground water is utilizedfor the production of heat of high temperature. In the upper'part of thecondenser-evaporator 52 an evaporator 55 of an indirect heat transfersystem is disposed, the evaporator 55 being provided with radiatingribs. the heat to the atmosphere. Both parts 55 and 58 are connected bythe transfer conduit 51 in which a check valve 58 is provided. In thisclosed system a liquid is placed which may transfer the cold prevailingoutside to the condenser-evaporator 52 by condensation in the condenser50 and by evaporation in the evaporator 55. .A

The corresponding condenser 58 radiatesA A similar heat-transfer systemau," 3| and 32 is arranged between the absorber-generator 44 and theground water level. A further heattransfer system 38, 40, 4I with avalve 42 disposed in the connecting 'conduit 40, connects thecondenser-evaporator 52 with the ground water. A still furtherheat-transfer system is disposed between the absorber-generator 44 and'the space 45 to be heated. Y

The system consists of the pipe 38 provided with cooling ribs andarranged in the absorbergenerator 44, the ends of said pipe beingconnected through conduits 34, 35 to the radiator 35 arranged in thechamber 4,5. In the conduit 35 a regulating valve 31 is provided. Thelowest point of the condenser-evaporator 52 is connected with the upperpart of the absorbergenerator by means of a drain conduit 41 in which avalve 46 is arranged. 'I'his valve must be opened at certain intervalsin order to cause the absorbing medium entrained from theabsorber-generator into the condenser-evaporator to flow back.

During the generating period the valves 42 and 31 are closed whereas thevalve 581s open. The absorber-generator is heated by ground water,whereas the condenser-evaporator is cooled by outside air. Consequently,the working medium is expelled from the absorber-generator and reachesthrough the conduit 53 the condenser-evaporator 52 where it iscondensed.

temperature, the other of said devices being so being also provided withtwo devices for the transfer of heat, one of said devices of thegenerator-absorber being so arranged as to transfer during the period ofcondensation heat from a medium of lower temperature to the generator- 5absorber, and the other of said devices of the generator-absorber4 beingso arranged as to transfer the heat of absorption to a medium to beheated.

2. In a system for the production of heat, 10 an apparatus of theintermittent ,absorption type, comprising a generator-absorber and acondenser-evaporator, said condenser-evaporator being provided with twodevices for the transfer absorption is transferred from theabsorbergenerator 44 to the space l5 to be heated.

The greater the difference between the temperature of the ground waterand the outside," temperature, the greater the amount of working mediumexpelled during the generating period will be, and the greater theamount of heat developed during the heating period, and the higher thetemperature, so that in the case of a lower outside temperature a highertemperature and also more heat is available for the space to be heated.

Instead of the heat existing in the ground water, any other waste heatsources maybe utilized for heating the generator and the evaporator. Insuch casesl also ground water may be used to advantage for cooling thecondenser.

We claim as our invention:

1. In a system for the production of heat, an apparatus of theintermittent absorption type, comprising a generator-absorber and acondenser-evaporator, said condenser-evaporator being provided with twodevices for the transfer of heat. one of said devices being so arrangedas to give up the heat of condensation of the wor ng medium to a mediumof lower to give up the heat of condensation of the working medium tothe cold outside air, the other of said devices being so arranged as totransfer the heat from the ground water to the condenser-evaporator forevaporating the work medium, said gen- V9 0 crater-absorber being alsoprovided with two devices for the transfer of heat, one of said devicesof the generator-absorber being so arranged as to supply during theperiod of condensation heat from the ground water tothe generator- 25absorber, and the other of said devices of the generator-absorber beingso arranged as to transfer the heat of absorption to a medium to beheated.

arranged as to transfer the heat from a medium of higher temperature tothe condenser-evaporator, means in said two devices for controlling thetransfer of heat, said generator-absorber EDMUND ALTENKIRCH. 30 KURTNEssELMANN.

of heat, one of said devices being so arranged as 15`

